To illustrate the operation of the second variable, the time for which the capital is advanced, let the same suppositions be continued, except that the _time of advance_ at New York be extended to four years. Then the commodity may be sold at and from Amsterdam, as before, at $103, but the corresponding commodity at and from New York for not less than $131, so far as mere cost of production determines the prices. This point is also well shown up in the case of wine, which, to reach its perfection, requires to be kept a number of years, for, if it be genuine and ripe, its cost of production has been by so much enhanced by its delay in reaching the market. If the time of advance be long, and the rate _per centum_ high at the same time, the cost of capital from the two causes combined multiplies the cost of the product; and consequently, only countries in which the _rates_ are low can successfully engage in enterprises requiring a large capital to be invested for _long periods_ before returns are realized. One million of Dutch capital at 3% a year, expecting to realize returns only after 20 years, may be remunerated by products selling for $1,806,111; but American capital under like circumstances, except that the rate here is 7%, must have a return of $3,869,685, or lose by the operation. To illustrate the action of the third and last variable, we must observe, that all forms of capital wear out, but some forms much faster than others, and that this makes a difference in the sinking-funds that must be reserved out of the gross profits of the capital in order to replace the principal whole. This difference will at once affect the cost of capital, and so of production, and so indirectly the ultimate value of the product. Suppose there are two commodities, which we will call A and B, produced in two different establishments, in each of which is invested a capital of $11,000, in one of which is used a machine that costs $1000 and is wholly worn out by one year's use, and in the other a machine costing the same sum, which will last, however, for ten years. Suppose further, that the rate _per centum_ of profit be 10, and the time consumed in completing each of the two products be one year. Now there is a marked difference in the Cost of Capital in the two establishments, and this difference will indirectly but immediately appear in the Value of the respective products. For, to A must be charged not only $1100, the interest on the whole capital at the current rate, but also another $1000, wherewith to replace the machine already worn out by a single year's use. A, accordingly, cannot be sold without loss for less than $2100. B, however, will cost less and can be sold for less at the usual profit. Because, to it must be charged, as before, $1100, current rate of profit on the capital invested, and only $100 (really less than that for an obvious reason) to replace the durable machine after ten years' use.